The overall objectives of the project are to examine the relationships among risk factors for cardiovascular disease in 541 women aged 42-50 at entry to the study in 1983-5, and changes in risk factors as the study participants experience the menopausal and the postmenopausal period. Among the risk factors measured are lipoprotein lipids and apoproteins, fasting and post-load glucose and insulin, sex hormones and gonadatropins, coagulation parameters, cigarette smoking, diet, physical activity, blood pressure, obesity, Type A behavior pattern, anger, social support, and anxiety. The protocol for the renewal proposal remains the same as for the original study design. Study participants will be tracked monthly via postcard for menstrual status. After 3 consecutive months without menstruation and/or being on hormone replacement therapy a perimenopausal exam is scheduled; after 12 months amenorrhea and/or taking hormone replacement therapy a postmenopausal exam is done and an age-matched premenopausal control is examined concurrently with each postmenopausal "case". Examinations are conducted annually on all postmenopausal women. All women are sent semiannual questionnaires on health-related behavior. It is important to continue the project because there is still a paucity of epidemiologic studies of cardiovascular risk factor changes and risk of heart disease related to natural menopause. The present study is one of the few in which premenopausal women are followed carefully through the climacteric with subsequent follow-up including detailed behavioral and biological measures, as well as important environmental variables related to the determinants of these risk factors.